Malaria is one of the deadliest global health threats, and remains a public health crisis, especially in sub-Saharan Africa. Despite major strides in treatment and prevention, the disease infects hundreds of millions of people each year and kills hundreds of thousands more. Children under five and pregnant women bear the brunt of the disease. Still, a breakthrough in malaria vaccine research means that there might be hope for those most at risk. In this article we’ll explore the latest developments in malaria vaccines, and whether they have a role to play in maternal and child health.
The Global Impact of Malaria
Malaria, caused by the Plasmodium parasite – transmitted by the bite of a female Anopheles mosquito – results in severe illness and death if untreated. The World Health Organization (WHO) estimated there to have been 247 million cases of malaria worldwide in 2022, with 95 percent of these cases being in Africa, children under 5 years of age being particularly susceptible, and pregnant women also being highly vulnerable due to changes in the immune system and hyper-susceptibility to severe disease.
The Role of Vaccines in Malaria Prevention
Vaccination remains one of our most successful interventions to stop the spread of infectious diseases. And we can see why that has not been the malaria case. The intricate life cycle of the parasite confuses the immune system, and the sophisticated set of measures Plasmodium uses to hide makes developing vaccines extremely difficult. Yet in recent years, a new excitement for the cutting edge of this research has brought about a ‘striking progression’ in understanding the possibilities of controlling and even eliminating the parasite.
Recent Advances in Malaria Vaccine Research
1. RTS,S/AS01 Vaccine
Mosquirix, or RTS, S/AS01 (produced by GlaxoSmithKline and the PATH Malaria Vaccine Initiative), remains the most advanced malaria vaccine to date, with decades of R&D and clinical trials behind it. In 2021, it became the first malaria vaccine to receive a WHO recommendation.
- Effectiveness: Mosquirix has proven, in clinical trials, to diminish cases of malaria by about 30 percent in very young children – a promising reduction, given the difficulty of developing a vaccine against a complex parasite like Plasmodium.
- Rollout: The vaccine is already being administered in several countries in Africa in so-called pilot programs. These will be useful for determining how the vaccine works in real life and collecting data on the new vaccine’s ability to reduce the incidence of malaria.
2. R21/Matrix-M Vaccine
The second is the R21/Matrix-M vaccine, an affordable, ready-to-use vaccine developed by researchers at the University of Oxford in collaboration with the Serum Institute of India. Like the malaria vaccine, it has also demonstrated high efficacy in a pivotal phase 3 clinical trial. This vaccine represents the most promising candidate for an approved malaria vaccine and could be the biggest advance in malaria vaccine development.
- Efficacy: the R21/Matrix-M vaccine was more than 75 percent effective, which is far better than current vaccines.
- Where it stands now: The vaccine is at the last stage before regulatory approval when released it could revolutionize malaria prevention.
3. Whole-Organism Vaccines
Another key line of research involves whole-organism vaccines, using live or attenuated parasites to provoke an immunological response – and ensure durable immunity.
- Plus points: They might be able to provide broad protection against various strains of malaria, and they could provide long-lasting protection with a relatively small number of doses.
- Obstacles: Obtaining live parasites and vaccines and then safely handling them through the diseases they cause and prevent poses major challenges.
The Impact on Maternal and Child Health
1. Reducing Malaria-Related Maternal Mortality
These changes in the immune system of pregnant women, along with other physiological changes during pregnancy, mean that pregnant women are more susceptible to severe cases of malaria. There are various consequences of malaria during pregnancy, including anemia, preterm delivery, and low birth weight. By preventing any malaria cases with a vaccine, the health risks faced by pregnant women and their babies would be dramatically reduced.
2. Protecting Young Children
Malaria remains one of the world’s deadliest childhood diseases, and kids under the age of five are most susceptible to severe malaria, which can lead to life-threatening complications and death. If a vaccine like Mosquirix or R21/Matrix-M can keep these young kids away from severe malaria, it could save lives and reduce the financial burden on health systems. These vaccines have the potential to facilitate longer-term health improvements, as protection started in early life tends to have a lasting impact.
3. Improving Maternal Health Services
Likewise, the advent of malaria vaccines could enhance the overall quality of maternal care services. With less expenditure going towards malaria care, health systems could divert those resources to other key areas of maternal and child care. Vaccination programs can also provide a setting for the use of other preventive health services, such as antenatal care and health education.
Challenges and Future Directions
While the development of malaria vaccines represents a significant advancement, several challenges remain:
- Distribution and Accessibility: getting a vaccine where it’s needed – particularly in the far reaches of the global south, where many communities lack access to immunization – requires good supply chains as well as effective health infrastructure and community engagement.
- Cost: In lower-income countries, the cost of the vaccine is still a bit of a barrier. Affordability and accessibility are important goals to pursue to help ensure as widespread use as possible.
- Public Acceptance: Community education and engagement, and refuting misconceptions, play a central role in achieving high vaccination rates. Maintaining belief in vaccination programs relies on addressing the public’s concerns.
Malaria vaccines hold the promise of improving maternal and child health Drinking fruits and feeding your babies may not stop them from getting the disease. However, when available, they are still the only intervention to prevent malaria in the general population. Beyond consumption, additional vaccines that can protect pregnant women and young children provide a welcome step forward in the fight against a disease that remains the world’s most fatal infectious scourge.
Global health agencies, governments, and communities must work together to make this promise a reality; we are on the way to a world free from malaria as a major cause of morbidity and mortality.
